Mini sextant lets you take sights anytime

Jan 1, 2003

A Swedish inventor renowned for his low-budget voyaging on unlikely craft of his own design has developed a new sextant that can be attached to a pair of eyeglasses.

Sven Lundin's miniature sextant, which retails for about $35, has no moving parts, but is used much like a standard sextant. After waiting for the sun to touch the horizon, the user of the so-called Brissextant carefully notes the time of the sight. Sight reductions can be made using H.O. 249 or a scientific calculator, according to Lundin.

Instead of a single sun being manually brought down to the horizon as on a standard sextant, when looking through the Brissextant one sees several suns.

"All you have to do is to wait until one of [the suns'] limbs is exactly on the horizon," Lundin explains in his Brissextant directions. "Then you take the time in the usual way, swinging the little Brissextant and all. After that you simply look up that specific sun in the altitude table, and there you have the angle of the observed altitude."

Lundin has found his sextant to be as accurate as a full-sized version whether it is attached to one lens of a pair of glasses or held in the hand. He is presently compiling a nautical almanac that is to be used in conjunction with the Brissextant. Contact him at Bris Småbåtslaboratorium I Lyse, Lerklevsmyren 6103, 45392 Lysekil, Sweden.